我是否需要 XMLHttpRequest 来使用 JavaScript 更改 JSON 文件值？

Question

So I'm trying to make a game where people can change their display name and then store it in a JSON file so that other files and pages can access it. So I added an XMLHttpRequest but I then read this article and wondered whether I actually need the XMLHttpRequest. I will attach the JavaScript and JSON files to give a bit more context.

JavaScript:

var console;
let requestURL = 'displayName.json';
let request = new XMLHttpRequest();
request.open('GET', requestURL);
request.responseType = 'json';
function sendRequest() {
request.send("displayName");
}
document.getElementById('displayName');
if (displayName = "") {
  displayName = 'Soldier';
}

JSON:

displayNameData {
  "displayName": ""
}

Answer 1

You need XMLHttpRequest or fetch to make HTTP requests.

Since your JSON is at the end of a URL, you need to use one of them to read it.

The question you link to has nothing, despite the title, to do with JSON. It is dealing with the manipulation of JavaScript objects .

Answer 2

If you want the JSON file to provide data to your application AND you want the javascript to update it, then you need to submit your request to a server-side handler that then generates the JSON file. Currently, your code will just return the static JSON file.

It is not clear what you are trying to do with this code.

Answer 3

If you want the user's browser to send information to your server, you need an HTTP request .
For this reason, they are very important to web development and worth your time to learn about.
Check out one or both of these resources to dive in:

• javascript.info - tutorial
• MDN - reference

Note that communication with the server generally happens asynchronously so the browser can keep working on other things until the server responds. Therefore, to notice when the server responds, you need to use either

• a callback function, or
• a Promise object (for which you can use async/await for convenience .)

Happy coding!